[llvm] [llvm-dwp] Replace MCStreamer with direct ELF writer for zero-copy output (PR #192112)

[Farid Zakaria via llvm-commits]

fzakaria wrote:

In our large-mono repo I noticed llvm-dwp taking a while when I investigated our buck2 (build tool) action graph.

https://github.com/llvm/llvm-project/pull/192112